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\IBVShead{4235}{28 August 1995}

\centerline{\ft COMPLETE PHOTOELECTRIC U,B,V LIGHT CURVES OF } 
\centerline{\ft THE SHORT PERIOD NEAR CONTACT SYSTEM: HL AURIGAE}
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\begintext

	The eclipsing variable, HL Aurigae (S4727 Aur), was discovered 
by Hoffmeister (1949) in a survey of Zone +40\degr\ Sonneberg plates for new 
variables.  He gave the variable a probable classification of an Algol-type 
(EA) eclipsing system which displayed a 1.0 magnitude amplitude but he gave 
no period.  Kippenhahn (1953) reclassified HL Aurigae as a Beta Lyrae-type 
binary from 96 plate estimates showing the primary and secondary eclipse 
depths to have 1.1 and 0.35 magnitude amplitudes respectively.  He also 
reported the first orbital elements which are given in Equation 1.
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\hspace*{25mm}    JD Hel Min. I = 2426365.309 + 0\fd 6225058 $\times$ E \hfill                   (1)
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Kippenhahn (1955) later published a photographic light curve and fifteen 
times of minimum light.  Pfau (1955a, 1955b) published two lists which 
included fourteen new minima, a finder chart, and a photographic light curve.  
Since that time, HL Aurigae has been monitored by many individuals 
(BBSAG \#21-\#103) who give timings of minimum light for this system.  
Zhang et al. (1994) give an informative IBVS note which includes eleven 
epochs of minimum light, BV photoelectric light curves, and the improved 
ephemeris given in Equation 2.
\vskip 1mm
\hspace*{25mm} JD Hel Min. I = 2447913.3470 + 0\fd 62250590 $\times$ E \hfill                (2)
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	Our present U,B,V light curves of HL Aur were obtained, as part of 
our survey of the eccentric eclipsing binary (EEB) candidates of Heged\"us 
(1988).  The observations were made on 1994, December 9-15 at Lowell 
Observatory, Arizona.  The 0.79-m National Undergraduate Research Observatory 
(NURO) reflector was used in conjunction with a thermoelectrically cooled 
S-13 type PMT.

	The approximate coordinates of the comparison, check, and variable 
stars are given in Table 1.
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\centerline{Table 1}
\begin{center}
\begin{tabular}{lcc}
\hline
		Star  &          RA\,(2000)  &               D\,(2000)\\
\hline
\\
	     HL Aurigae  &      6\fh 19\fmm 08\fss 5   &     49\degr 42'22''\\
	     Comparison    &   6\fh 19\fmm 16\fss 4   &     49\degr 21'53''\\
	     Check          &  6\fh 18\fmm 59\fss 4 &     49\degr 24'59''\\
	   \hline
\end{tabular}
\end{center}
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	We determined four new precise epochs of minimum light from 
observations made during three primary and one secondary eclipse.  The 
Hertzprung method (Hertzsprung, 1928) was used to determine the first two 
primary minima while the bisection of chords technique was used to determine 
the last primary epoch of minimum light.  The secondary minimum was determined 
using the bisection of chords technique as well as a hybrid of this
\break

\centerline{2}
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Figure 1. Photoelectric U, B light curves of HL Aurigae as defined by the 
individual observations.
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\centerline{\epsffile{4235-f2.ps}}
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Figure 2.  Photoelectric  B, V light curves of HL Aurigae as defined by the 
individual observations.
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\centerline{3}
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\noindent method 
which allows analysis of asymmetric eclipses.  These are listed in Table 2.  
In Table 2, values are accompanied by their 
probable errors in parentheses.

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\centerline{Table 2}
\begin{center}
\begin{tabular}{ccrr}
\hline
	JD Hel. 2400000+    &    Eclipse Type  &      Cycles &         O$-$C\\
\hline
\\       
	49695.8909(3)  &  II   &         $-$1.5  &          $-$0.0005\\
	49695.8924(3)  &   \ \,II$^{\star}$  & $-$1.5&             0.0010\\
	49696.8232(1)  &    I  &  0.0        &   $-$0.0019\\
	49698.6900(7)  &    I  &          3.0  &        $-$0.0027\\
	49701.8021(5)  &    I  &           8.0 &           $-$0.0031\\
      \hline
 \end{tabular}
\end{center}
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 $^{\star}$ indicates minima determined with hybrid method
	
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	All available epochs of minima were introduced into a least squares 
solution to obtain a new ephemeris which best represents the present 
observations:
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 \hspace*{25mm} JD Hel Min. = 2449696.8251 + 0\fd 6225049 $\times$ E \hfill             (3)
\hspace*{7.7cm}$\pm$12\ \hspace*{17mm}$\pm$4
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The O$-$C residuals calculated from Equation 3 are listed as O$-$C in Table 2.

	The U, B, V light curves of HL Aurigae as defined by their individual 
observations are shown in Figures 1 and 2 as differential magnitudes 
(variable$-$comparison) versus phase.  This system does not show a displaced 
secondary in either the present precision observations or those of Zhang et 
al. (1994).  This casts doubt on the validity of this variable being 
classified as an EEB.  A thorough analysis of the observations is in progress 
and will be reported on elsewhere.
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\beginauthors
\authorsrightcol
Jamison D. GRAY$^{1,2,3}$
Ronald G. SAMEC$^{1,2}$
Department of Physics and 
Astronomy
Millikin University,
Decatur, Illinois  62522 
USA
\endauthors
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\noindent$^1$  Visiting Astronomer, Lowell Observatory, Flagstaff, Arizona.

\noindent$^2$  This research was supported by funds from the National Science Foundation.

\noindent$^3$  This research was partially supported by funds from the Leighty Science Scholarship Program.

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\references

Heged\"us, T., 1988, {\it CDS Bulletin}, {\bf 35}, 15

Hertzsprung, E., 1928, {\it Bull. Astron. Inst. Neth.}, {\bf 4}, 179

Hoffmeister, C., 1949, {\it Astr. Abh. AN}, {\bf 12}, (1), 22

Kippenhahn, R., 1953, {\it Nachr. der Astr. Zentralstelle}, {\bf 3}, 11

Kippenhahn, R., 1955, {\it AN}, {\bf 282}, 73

Pfau, W., 1955a, {\it MVS, Sonneberg}, No.\,198

Pfau, W., 1955b, {\it MVS, Sonneberg}, No.\,199

Zhang, R., Fang, M., Zhang, J., and Zhai, D., 1994, {\it IBVS}, No.\,4098


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